This invention relates to ladles for pouring molten metal in metal casting operations.
In the die cast industry, ladle cups are employed for transferring and pouring molten metal. These ladles deteriorate with prolonged use due to chemical and thermal stresses produced thereon by the high temperature of the molten metal which rapidly burns holes in the ladle walls. Even with routine maintenance, conventional ladles have a relatively short useful life such that frequent repair and/or replacement thereof can be very expensive.
Furnaces for melting metal and containers for molten glass have employed high-temperature resistant refractory materials as described, for example, in U.S. Pat. Nos. 3,916,047 and 2,947,114. In efforts to prolong the useful life of a ladle for pouring molten metal, it has been known to use a lining of refractory materials, such as described in U.S. Pat. Nos. 4,330,107 and 2,967,339.
However, it is known that use of a refractory lining in these ladles is not adequate because the lining is eroded as a result of repeated charging and pouring of the molten metal. U.S. Pat. No. 4,330,107 describes a ladle in which the interior refractory lining is fabricated as a sleeve which must be periodically replaced; further such a sleeve device requires special retaining clips or rods to hold the lining sleeve in place, particularly when the ladle is tilted. The primary disadvantages of short life for the prior art ladle structures, including special clips or other retainer devices are eliminated by the herein invention.